Disposable food tray

ABSTRACT

A disposable food tray that includes one or more strength-enhancing features to increase the strength and rigidity of the tray is provided. For example, in one embodiment, the disposable tray includes an inner wall that is curved and that includes a curved recessed portion. If desired, the corner sections of the tray can be provided with a ledge to improve the strength and ability of the trays to be stacked and shipped without breaking or bending. In one embodiment, the tray is also formed from a microcellular-foamed polystyrene material that can further enhance the strength and rigidity of the resulting tray.

BACKGROUND OF THE INVENTION

[0001] In many food service operations, it is often beneficial to utilize food service trays that are disposable. For example, disposable food trays can allow the food service provider to hire fewer workers and can help maintain the cleanliness of the kitchen area due to the fact that dirty trays need not be returned to the kitchen and washed. In fact, in environments where many people must be served in a relatively short period of time, such as in a school cafeteria, disposable food trays have virtually replaced re-usable metal and plastic trays.

[0002] Despite the benefits achieved by using disposable food trays, problems nevertheless remain. For example, conventional disposable food trays are often too “flimsy” to adequately support the weight of the food and beverages on the tray. Thus, when carried, the tray can bend or even break, thereby causing the food or beverages to fall off of the tray. This has proven to be an especially difficult problem in food service areas involving children, mainly because children's hands are usually not large enough to provide the extra support needed to ensure that such a flimsy food tray will not bend or collapse.

[0003] In addition to problems with strength and rigidity, conventional disposable foam food trays have also experienced problems with securely holding the individual items served with a meal. For example, in a school cafeteria, milk is often provided in a new Echo® brand half-pint container. Although most conventional disposable trays are formed with one or more compartments for such beverages, these compartments typically only loosely hold the container in position. Thus, this loosely held beverage container is free to slide, which can allow the beverage to tip over or fall entirely off of the tray.

[0004] As such, a need currently exists for a disposable food tray that is rigid and sturdy and that can adequately hold food and/or a beverage container and yet conform to various specifications such as length, width, thickness, weight, and cost.

SUMMARY OF THE INVENTION

[0005] In accordance with one embodiment of the present invention, a disposable tray is provided for holding a food item or a beverage container. The disposable tray includes a base portion having an upper surface and a lower surface that define a peripheral edge. A sidewall extends upwardly from the peripheral edge of the base portion to form an upper edge of the tray. In one embodiment, the sidewall defines at least one rounded corner that may include a ledge portion that is substantially parallel to the upper surface of the base portion. Moreover, in one embodiment, at least a portion of the upper edge of the sidewall defines a rounded lip.

[0006] The disposable tray also includes a first inner wall and second inner wall that are disposed within the periphery of the base portion and extend upwardly from the upper surface of the base portion. In one embodiment, one of these inner walls is curved. In addition, at least one of the inner walls defines a curved recessed portion that is capable of enhancing the strength of the tray.

[0007] In addition, the tray includes first and second compartments defined by the base portion, the sidewall, the first inner wall, the second inner wall, or combinations thereof such that a food item or beverage container is capable of being disposed on the upper surface of the base portion within the first compartment and the second compartment.

[0008] Other features and aspects of the present invention are described in more detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] A full and enabling disclosure of the present invention, including the best mode thereof, to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:

[0010]FIG. 1 is a perspective view of one embodiment of the disposable food tray of the present invention;

[0011]FIG. 2 is a top plan view of one embodiment of the disposable food tray of the present invention;

[0012]FIG. 3 is a cross-sectional view of the disposable food tray shown in FIG. 2 taken along a line 3-3; and

[0013]FIG. 4 is a cross-sectional view of the disposable food tray shown in FIG. 2 taken along a line 4-4.

[0014] Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the invention.

DETAILED DESCRIPTION OF REPRESENTATIVE EMBODIMENTS

[0015] It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present invention, which broader aspects are embodied in the exemplary construction.

[0016] The present invention is generally directed to a disposable food tray that has enhanced rigidity and strength in comparison to conventional disposable food trays. For example, in one embodiment of the present invention, the disposable food tray contains at least one wall having a curved surface to enhance the structural rigidity to the tray. Moreover, the disposable tray of the present invention can also be formed such that liquid containers, such as soup or beverage containers, fit within the tray, thereby inhibiting tipping or spilling. In addition, it has been discovered that such structural rigidity and strength can be achieved without significantly increasing the weight of the resulting tray, which is typically between about 9 grams and about 11 grams. In one embodiment, the tray can weigh about 10 grams.

[0017] Referring to FIGS. 1-4, one embodiment of the disposable tray of the present invention will now be described in more detail. As shown in FIG. 1, the disposable tray 10 includes a sidewall 12 that extends upwardly from the periphery of the base portion 14 of the disposable tray 10 to form an upper edge 34. In this embodiment, the base portion 14 and the sidewall 12 are formed as a single, continuous structure. It should be understood, however, that the base portion 14 and the sidewall 12 may be formed from separate sections that are attached in any manner known in the art. In addition, in the illustrated embodiment, the sidewall 12 is disposed at an angle to the base portion 14 to facilitate stacking of the trays during storage and shipping. For instance, the sidewall 12 can be disposed at an angle of from about 10° to about 45° from an axis that is perpendicular to the base portion 14. In one particular embodiment, the sidewall 12 can be disposed at an angle of about 32.5° from an axis perpendicular to the base portion 14.

[0018] In general, the dimensions of the sidewall 12 and/or the base portion 14 can vary depending on the type of food and/or beverage the tray 10 is designed to carry. For example, in some embodiments, the height dimension “h” (shown in FIGS. 3-4) of the sidewall 12 can be less than about 2.0 inches, and in some embodiments, less than about 1.50 inches. In one embodiment, the height “h” of sidewall 12 can be about 1.16 inches. The overall shape of the disposable tray 10 can also vary. For example, in one embodiment, as shown in FIG. 2, the disposable tray 10 can have a generally rectangular shape with four rounded corner sections 16. For example, when used in a school setting, the base portion 14 of the rectangular-shaped disposable tray 10 can have a length dimension “I” of about 10.375 inches and a width dimension “w” of about 8.375 inches. However, it should also be understood that the tray 10 can have other shapes as well, such as a circular shape.

[0019] Referring again to FIGS. 1-2, the disposable tray 10 also includes a plurality of inner walls 26 contained within the periphery of the base portion 14 that divide the disposable tray 10 into various compartments. As shown in FIG. 4, for example, the inner walls 26 that form the various compartments extend from the base portion 14 and have a height “i” that is typically less than the height “h” of the sidewall 12. For example, in one embodiment of the tray 10, the height “i” of the inner walls 26 can be about 0.560 inches.

[0020] Generally, the number and type of compartments may be varied in any manner desired. For example, in some instances, the number and type of compartments can be determined in accordance with the specified use of the disposable tray 10. In this regard, one embodiment of the disposable tray 10 is shown in FIGS. 1-4 that contains food compartments 21, 22, 23 and 25 and a beverage compartment 24. This five-compartment disposable tray 10 may be particularly useful in a public school setting. As shown, the food compartments 21 and 22 are relatively large. These relatively large food compartments 21 and 22 can vary in size. For example, in one embodiment, the compartment 22 includes a roughly square-shaped portion having length and width dimensions of approximately 3.0 inches. This particular size can allow the standard-sized soup bowl (having a base diameter of approximately 3 inches) used in most school lunch programs to be securely held within the compartment 22 without slipping. In addition, the compartment 22 also includes a semi-triangular shaped inset portion 35, which is created by the angled wall 26 between the compartments 21 and 22. This inset portion 35 can facilitate the insertion and removal of a bowl within the compartment 22, and also provide a space large enough so that a person can insert his/her fingers into the compartment 22 to securely grasp a container contained therein.

[0021] In the illustrated embodiment, the food compartment 21 is the largest food compartment, having dimensions of, for example, 2.682 inches by 3.912 in the rectangular portion of the food compartment. The food compartment 21 also contains an inset portion 37, as shown in FIG. 2. The added size of the inset portion 37 can allow the food compartment 21 to adequately contain a large volume of a food serving, such as for example, a meat serving.

[0022] In addition, the disposable tray 10 also includes a beverage compartment 24. For example, many school lunch programs serve milk in a carton (e.g., the Echo® milk carton) having known dimensions. Thus, the compartment 24 can be formed to match this size in order to securely contain the milk carton and help prevent the carton from tipping or slipping while the tray is being carried. In addition to holding the beverage container tightly, limiting the size of the beverage compartment can also allow the other food compartments to be formed somewhat larger than conventional disposable trays. For example, the beverage compartment 24 can have minimum inner dimensions of approximately 2.0 inches by 2.0 inches in order to tightly contain a beverage container of known, similar dimensions.

[0023] If desired, the beverage compartment 24 can also include a ridge 27 near the bottom of the compartment such that the beverage compartment 24 can be slightly larger above the ridge 27 than below. The presence of the ridge 27 can allow for the equally secure containment of beverage containers of more than one size in the beverage compartment 24. For example, the dimensions of beverage compartment 24 can be such that a particular beverage container can sit on the base portion 14 of the compartment 24 and be tightly held within the ridge 27 of the beverage compartment 24.

[0024] Alternatively, a different beverage container, having slightly different dimensions, such as a cup or bottle, could sit in the same beverage compartment, but sit on the ridge 27 and be tightly held by the upper walls of the beverage compartment 24. The same disposable tray could thus tightly contain either the larger beverage container on top of the ridge 27 or a smaller container between the ridge 27.

[0025] Recently, the Echo® brand milk container has become popular, particularly in school lunch programs. This type of container has shown a tendency to ‘wobble’ when placed on conventional disposable food trays. Ridge 27 can not only support the outer edge of such a beverage container, it can allow the rounded bottom of the milk carton to have adequate clearance and contact the base portion 14 at the middle of the carton base yet also fit within the upper walls of beverage compartment 24. This can stabilize the milk carton and prevent the milk carton from wobbling in the tray.

[0026] The remaining food compartments of the disposable food tray 10 can also be optimized according the service requirements of the trays. For example, in the embodiment shown in FIGS. 1-4, the food compartment 23 can have inner dimensions of approximately 2.141 inches by approximately 2.406 inches and be used to contain a food item that is relatively small in volume, such as, for example, a dessert. The food compartment 25 can have slightly larger dimensions, such as approximately 2.141 inches by 2.519 inches and be used to contain, for example, a vegetable. Of course, the various food and beverage compartments of the disposable food tray of the present invention can contain whatever items desired by the user.

[0027] In accordance with the present invention, the disposable tray also includes various structural components that can improve the strength and rigidity of the tray, as well as allow the tray to more securely hold food and beverage containers. Additionally, it has been discovered that such structural components can enhance the strength of the tray without requiring a substantial increase in the weight of the relatively, lightweight tray structure (e.g., less than about 20 grams). For example, in one embodiment, as shown in FIGS. 1-4, the inner wall 26 between the compartments 21 and 22 contains two side sections 53 and 55 that extend upwardly from the base portion 14 at the same or a different angle, where they converge to form an upper section 51 of the inner wall 26. As shown, the side sections 53 and 55 generally curve from one end 57 of the wall 26 to the other end 59. It has been discovered that such a curved inner wall structure can provide the resulting tray 10 with enhanced strength and rigidity.

[0028] In addition, in some embodiments, one or more inner walls 26 of the disposable tray 10 can have a recessed portion 20. For example, in one embodiment, the disposable tray 10 can contain a recessed portion 20 that is formed within the upper section 51 and side sections 53 and 55 of the inner wall 26 located between the compartments 21 and 22. As shown in FIG. 4, the recessed portion 20 is generally curved so as to provide increased strength and rigidity to the inner wall 26. Although not required, the recessed portion 20 can be formed as a continuous structure and from the same material as the remainder of the tray 10.

[0029] Besides the above-mentioned structural components, the disposable tray of the present invention can also contain other features that are capable of enhancing its strength and rigidity. For instance, referring to FIGS. 1-3, in one embodiment, a ledge 30 can be formed in one or more of the rounded corner sections 16 of the disposable tray 10. As shown, the ledge 30 is formed into the sidewall 12 and is located approximately half the distance between the base portion 14 and the upper edge 34 of the sidewall 12. The ledge 30 is substantially parallel to the base portion 14 and may be formed at a constant width or may vary in width as the ledge 30 proceeds around the rounded section 16 of the tray 10. For example, in some embodiments, the ledge 30 can have a width dimension “a” of from about 0.05 inches to about 0.25 inches, and in some embodiments, between about 0.10 inches to about 0.20 inches. In one particular embodiment, the ledge 30 can have a width “a” of approximately 0.16 inches.

[0030] The ledge 30 can improve the rigidity of the disposable tray through the rounded corner sections 16. In effect, the presence of ledge 30 can divide the total height “h” of the sidewall 12 into a lower portion below the ledge 30 and an upper portion above the ledge 30. It has been discovered that by effectively dividing the height of the sidewall 12 in such a manner, the strength and rigidity of the sidewalls 12, particularly around the corner sections 16, can be increased.

[0031] Moreover, not only can the ledge 30 add strength and rigidity to the disposable tray 10, but it can also improve the ability of disposable tray 10 to be stored and shipped. For example, the ledge 30 can provide support for the tray when many multiple trays are stacked together in a nested fashion. The ledge 30 can also help prevent breakage of the trays due to overzealous packing. For example, in the past, when trays are tightly nested one inside another, it was possible to push the trays together too tightly causing the outer walls to crack. Due to the presence of the ledge 30 on the disposable tray 10, however, multiple trays can be tightly nested without fear of breakage, since the bottom of the upper trays are held at the ledges and thus prevented from sliding too far down into the lower tray in the stack and cracking the walls.

[0032] Furthermore, the disposable tray 10 can also contain other strength-enhancing features as well. For example, in one embodiment, such as shown in FIGS. 1-4, the sidewall 12 can define a rounded lip at its upper edge 34. As shown in FIG. 3, for example, the edge lip is defined by a rounded top 36 and an extension 38. The extension 38 can be substantially straight and parallel to the base 14, as shown in FIG. 3, or alternatively, can be slightly rounded. In one embodiment, the extension 38 can extend outwardly approximately 1 mm from the outer edge of rounded top 36. When utilized, the curvature of a rounded top 36 can add rigidity to the sidewall 12 of the disposable tray 10 and help to prevent it from folding or breaking when supporting the weight of items placed in the various compartments. For example, when fully loaded with food and supported at an end of the tray, the weight of the food can cause an unsupported upper edge 34 to crack perpendicularly across the edge. By utilizing the rounded top 36 and the extension 38 on upper edge 34, the weight of the food can be mitigated over the curvature of the rounded top 36 and upper edge 34 can typically show less of a tendency to break and/or crack.

[0033] In general, the disposable tray of the present invention, such as described above, can be formed from one or more of a variety of different types of materials. For example, the disposable tray is typically formed from a material that possesses strength and ductility, and that is also environmentally friendly, e.g., materials that contain no chlorofluorocarbons (CFC's or HCFC's) and no gaseous hydrocarbons. Moreover, it is typically desired that the materials used to form the tray should be able to hold hot food (e.g., temperatures of up to about 200° F.) without damaging the tray or without causing the food to leak through. Examples of suitable materials that can be used to form the disposable tray of the present invention include, but art not limited to, paper, cardboard, foamed materials, and the like.

[0034] In one particular embodiment of the present invention, microcellular-foamed materials can be used to form the disposable trays. Microcellular-foamed materials generally include materials that possess homogeneous microcellular cell sizes of less than about 50 microns and/or materials that have cell densities of from about 10⁹ to 10¹⁵ per cubic centimeter of material. For instance, in one particular embodiment, the disposable tray of the present invention is formed from a microcellular-foamed polymer material such as a microcellular-foamed polystyrene material. It has been determined that such microcellular-foamed polystyrene materials are relatively strong and lightweight, and thus can further add to the strength and rigidity of the disposable tray of the present invention. Microcellular foamed products can also display good ductility, allowing the product to bend farther than conventional foamed materials without failure.

[0035] Microcellular-foamed materials can generally be formed in a variety of different ways. For example, such materials can be formed with carbon dioxide introduced into the plastic to form voids, which can help inhibit the presence of any potentially hazardous chemicals in the tray material. Various processes for forming microcellular foams are described in more detail in U.S. Pat. Nos. 4,473,665 to Martini-Vvedensky et al.; 5,158,986 to Cha et al.; 5,160,674 to Colton et al.; and 5,334,356 to Baldwin et al., which are incorporated herein in their entirety by reference thereto for all purposes.

[0036] Of course, other foamed materials may also be used to form the trays of the present invention. When forming a tray from a foam material, such as the microcellular-foamed materials described above, such materials can be processed using conventional techniques to form the resulting tray. For example, in one embodiment, the foamed material can be extruded and then thermoformed to shape the resulting disposable tray.

[0037] Regardless of the type of material utilized, the disposable tray of the present invention may be formed as a single, continuous structure. Typically, it is desired that the disposable tray be formed from a single, continuous structure to provide added strength and rigidity to the resulting tray.

[0038] These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention, which is more particularly set forth in the appended claims. In addition, it should be understood that aspects of the various embodiments may be interchanged both in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to limit the invention so further described in such appended claims. 

What is claimed is:
 1. A disposable tray for holding a food item or a beverage container, said disposable tray comprising: a base portion having an upper surface and a lower surface that define a peripheral edge; a sidewall extending upwardly from said peripheral edge of said base portion to form an upper edge of the tray; a first inner wall disposed within the periphery of said base portion and extending upwardly from said upper surface of said base portion, wherein said first inner wall is curved; a second inner wall disposed within the periphery of said base portion and extending upwardly from said upper surface of said base portion; first and second compartments defined by said base portion, said sidewall, said first inner wall, said second inner wall, or combinations thereof, wherein a food item or beverage container is capable of being disposed on said upper surface of said base portion within said first compartment and said second compartment; and wherein at least one of said inner walls defines a curved recessed portion that is capable of enhancing the strength of the tray.
 2. A disposable tray as defined in claim 1, wherein said side wall defines at least one rounded corner.
 3. A disposable tray as defined in claim 2, wherein said rounded corner includes a ledge portion that is substantially parallel to said upper surface of said base portion.
 4. A disposable tray as defined in claim 1, wherein at least a portion of said upper edge of said sidewall defines a rounded lip.
 5. A disposable tray as defined in claim 1, wherein the tray is formed as a continuous structure.
 6. A disposable tray as defined in claim 1, wherein the tray is formed from a microcellular-foamed polymer.
 7. A disposable tray as defined in claim 1, wherein the tray is formed from a microcellular-foamed polystyrene material.
 8. A disposable tray as defined in claim 1, wherein at least one of said inner walls has an end that extends from said sidewall.
 9. A disposable tray as defined in claim 1, further comprising a third compartment.
 10. A disposable tray as defined in claim 9, wherein at least one of said first, said second, or said third compartments includes a ridge for securely holding a beverage container.
 11. A disposable tray for holding a food item or a beverage container, said disposable tray comprising: a base portion having an upper surface and a lower surface that define a peripheral edge; a sidewall extending upwardly from said peripheral edge of said base portion to form an upper edge of the tray, said sidewall defining at least one rounded corner that includes a ledge portion that is substantially parallel to said upper surface of said base portion; a curved inner wall disposed within the periphery of said base portion and extending upwardly from said upper surface of said base portion, wherein said curved inner wall further defines a curved recessed portion that is capable of enhancing the strength of the tray; and first and second compartments defined by said base portion, said sidewall, said inner wall, or combinations thereof, wherein a food item or beverage container is capable of being disposed on said upper surface of said base portion within said first compartment and said second compartment.
 12. A disposable tray as defined in claim 11, wherein at least a portion of said upper edge of said sidewall defines a rounded lip.
 13. A disposable tray as defined in claim 11, wherein the tray is formed as a continuous structure.
 14. A disposable tray as defined in claim 11, wherein the tray is formed from a microcellular-foamed polymer.
 15. A disposable tray as defined in claim 11, wherein the tray is formed from a microcellular-foamed polystyrene material.
 16. A disposable tray as defined in claim 11, wherein at least one of said inner walls has an end that extends from said sidewall.
 17. A disposable tray as defined in claim 11, further comprising a third compartment.
 18. A disposable tray as defined in claim 17, wherein at least one of said first, said second, or said third compartments includes a ridge for securely holding a beverage container.
 19. A disposable tray for holding a food item or a beverage container, said disposable tray being formed as a continuous structure from a microcellular-foamed polymer material, said disposable tray comprising: a base portion having an upper surface and a lower surface that define a peripheral edge; a sidewall extending upwardly from said peripheral edge of said base portion to form an upper edge of the tray, wherein at least a portion of said upper edge of said sidewall defines a rounded lip, said sidewall defining at least one rounded corner that includes a ledge portion that is substantially parallel to said upper surface of said base portion; a curved inner wall disposed within the periphery of said base portion and extending upwardly from said upper surface of said base portion, wherein said curved inner wall further defines a curved recessed portion that is capable of enhancing the strength of the tray; and first and second compartments defined by said base portion, said sidewall, said inner wall, or combinations thereof, wherein a food item or beverage container is capable of being disposed on said upper surface of said base portion within said first compartment and said second compartment.
 20. A disposable tray as defined in claim 19, further comprising a third compartment.
 21. A disposable tray as defined in claim 20, wherein at least one of said first, said second, or said third compartments includes a ridge for securely holding a beverage container. 